Theead-cttttistg mechanism



. A. F. FIFIELD.

THREAD CUTTING MECHANISM FOR SEWING MACHINES.

APPLICATION FILED APR. 8. I914.

v Patented Dec. 7, 1915.

WI TN E 8858: 7%4 751m coullun WRAP" co.,munmcfon. n.c.

.A n rimm gim e, new Jiins gzz 'sicmGigflM ANY brCORPORATIONzQF NEW .rnnsny.

To elt-wbiam-it-mey concern: i fie -it lmown thet 12; ALBERT F.='Frrmnn,' a oiliiizen of the United States residing at Eliz a'beth in the county of Union and State =5 ence' being 3 lsingileemtatien to 'a needle and e coiiperetingshiittle acting'in wnjunhtion: with j stitable feeding: 1 mechariisrfn to prodnbe s'tnaighteway' s-titehing; combined? 1 with 1 thread} cutting 1'n'ec h'enisin arranged .th'e throat-plate and adapted to; sever one er bath; of the stitching mbhine is -provided with st p mttien eentmi le'd in its actionby starting lever, and has a; eoiitrbllin'g tam performing plurality er -stit ch=' feninilig eyclesw I I heq cbnstantly moving controlling cam impart's reeiprocetory movements -''to a," tel lower edeptedwe be connected bye spriiig f actuabiedfiiupling elenient with bne-ex in e 'ivi'brzrti'ery' lever' for imparting the mine-1';

or thread-positioning stages of movementof the threadeutting'elementsg- The-caniis peovided-with iheens ear retracting the cou' 1 pling element whieh is normeljly retained-in inopei ative" peeitien by m ans "of w springdetent'operetiveliy ceflfiected with the-*start in g 'lever and held by the-letti' disengagedfrom the coupling element-during the runnin'gwof: the'maehiner -The coupling elementhas connected therewith a shifting can for at tripping pinii ormelly disposedjn operative relation wlthg one erm of e detent;-

lever whose other aim detains a, vibratory L stop lever' ofthe stop-motion in running po-= Ositioin -'I'he tripping pin is periodical-l5 acted upon by a tripping point upon' the controllingcam, but when the starting lever is in running position the tripping pinremains shifted out of operative relation with e ss lenon. To THE SINGER MANU- "mmieiceehse mneiin'msni, non. sewmemcnme.

Patented Dee. 7,1915.

' A plic tion fiieah'pm', 1914. -Seril1(6.'8 30,344.

the stopotion detent-lever, and acts idly without je'fiect upon the stop-motion.

The final or thread-severing stage of movement of' the cutting elements is produced in a manner well-known by a connec tion of the stop-lever with the cutting mechenism, such movement being eflected by the overthrow of the stop-lever under the momentu-nr of the machine while coming to rest. 1 the eecompanying drawings, Figure '1' ifs' eperspective-view of a sewing machine provided =-"vvit'h the present "improvement, takenfrom the re'arside, and showing oer taz'inview, taken from the opposite side, of'the' threadcutter andstop motion controlling devices,- and showing these parts in different reletionlfrom that 'of Fi'gs 1'. 'Fig. 3 i's a perspective view showing detached the camfo'llower' 'leven; the cutter-actuating lever and the eou plingel'enient for connecting the same-togethen- ;-"-1 he lm eehfine is shown constructed with parts in section. Fig, 2 is a erspective the-usualbed plete 1; and-'brecketermfl Y the up er-member of which 7 is I journaled the main-S aft carrying upon its rearwardend the fast 'and loose pulleys 4 il'l'ldf th ef he d-of the bracket-arm is jour chef-usual rectilineari'y reciprocating needle= bar-' 5 havin the usu'el operative connection with-themaiir-sheft 3 (not shown) and calr= r ying theeye-pointed needle 7 cooperating in the production 'of stitches with the oscill'atin' shuttle 8 in practice -m'ountedin 'a suite le ra-ceway and deriving its operative movements from the shuttle-driver 9 upon the rock shaft 10 disposed beneath the bed plate and having the usual connection the main-shaft. v The feeding mechanism is of well-known form, comprising an eccentric upon the main-shaft embraced by the-yoked upper end of-the link-bar 11 "connected with'ii n arni of the feed rock-shaft 12. disposed beneathfthe bed-plate and'provided with the spaced upri hearms 13 towhich is pivotally attached the feed-bar '14 carrying the feed dog 1'5 extending through a suitable apert-u-re in the throat-pletelfi. -In general con-' struction and mode of operation the threadcutting mechanism and stop-motion are substentially as shown and described in the.

United States Patent to J. J.

Sullivan No. 777,564, of December 13. 1904:.

Pm fled ele n-i e lin chfa ewi h the notch 17: a normally entered bfi-iihfi j iwedg e eh fiaze r m y 1 ei t e de e tsl n' mell li mmn t e' ul r m $1 11. erewv a; and; pressed nc n a y n operati eirelation witht esteel ver y m a scith p ng 5-- The: leerwa t lm p eie i ap ntfi 07 h ee etz emr-is men d on! t ar-Wand ed e w th 2 s w-having h 'pr l me st dr erw rfij .enter -ee he elpeea ed p mme'ig n the; lidea 2 Pm ded t with ereeeedmer elm be hne dein aidzsc ket-bymeans; qf a BElng-:=33; 1111 thear; 29 i One e it If the; pin 'qggplgg .31 ';is;,-ada-Pted1z Ion. eeegem ntmitlii the :fenwarmymtendine emhz fl herglete tvlee 33; w'hi-1e1 epp 2- 5 emfiliesimm hermunali petha inwvem of one of the inclined trippihg1=plat si34ase= cu ed nppn the-inne t me n theimt ncontrekk ng-m me}?! The h h-36s ofnfi ismmfitFCd-mE-RQQ: th he b. I i the peripherally:

11: 0n the fil wl mg stud 'ile ixed linfl -hevabrael ete 33 113 lldnw hefl er eflweel Wee-th e tp-re e ze by means;

dime-125. 1 3 535- 119 2g nh ela38-me he i h a-re nion 449 fixeda pnng oneeemiie rthe lentha t e1 ha g pm: e-e peeiteend: 'he-=:b e rwh;ee AQ meShingH iG he ev l p nie e-efimhi hfle-fix si: p nnthe. and-ic gemunm teet gb e v-eamwheei w:- 35 :thi l gh' h e fi f-q nn eti nsene-mr whe fem emfm e ity Qfwarmsee he mgae-shei -en em q en rz rpl ee y e f stltch-forming cycles. w ;i'T- ,e?i mhas face; t

.1; wee- 9 W it? e tere 'bv e-t sii lewen ni-thge jen e ana e dependi ag arme i e d i ewe d y e t nd eem -f -ffihei huh v e q e -1. 50; fisefiweskie Wa t rh -p rt q e d-ie m e menth latter with a transversely apertnred bpss; 53 embraced by the;.-= simi;l arly apertnred lateral members 54 6f the channeled chl pl ingg lever 55 adapted t0 receive'the oi'lter p'brti'on 0f the lever 50 Within its channel, as representedI-in Fig.2; :filfhe ecupliirg levee-wheat ntally sustainedh? fihhp'ertured boss 53 of the rock-leyer arm fi O by means of the Secured upon the rearward face 91' the coupling lever 55 by means of serws 157% the cr0ss;;mem h er ofa lateral arm 59 carryirig the stud-screw 60 and having secured thereto by xneane;- qf the tasten'ing screw 61 he l e a i part san. Q i a-hent wire peeing thrgugh the :arm '59 l and? extending;- tihieren 20m: et-e e ygin thefcrm ofa pimfiz which so e e szianz perture'in then-lower: portie'n et- 1 the slide-bar 29 and serves t connect the slid =ba ith-the .fiOllBhfgilQY 55.- i 1: z: As Shawn and desc ibedzmone fullyiirtbe seidlre en p Z7 ,5 35| 4h thr wplatehas mounted therein the fulcrum-pin 63;;f0r'th oeqillatpry carrier fie t'awhictrenstainstipper end. lo erth ad l t znginimsk 5 66,; e81 6tie lywJEhe ce ienefif iiis-, dp rm iaelyleq-n e ted wi z laterahirme fi' hi the 9 reciprocatory bar ,63-;;m k mteh in i: g.14 d% eneath th 1 hertz-pla e an pm ided wit a eml ferhw entered by -thefts? n eelewe i arm. A9; cf the utter-ed cating o eev ar; 68;'ie='n0rme1ly= drawn qrward y by m ans eli th jsjpningtm-haeingl u its ea-rwa-rd and et eQh d-Wtsmd bar land itefenwerd ndisemi i k e one cf thelbe rimga t wps- 51;;by whi h it is eepp rhed; e eath; thehed-plate, 'ZBYfifil-IB actionfof the spring,- 70 the forward edge of the arm wisrncr'e meltv m inminedri ncen t With-the ivuistebl zpeint i the. t pcrew 172mouatednthe RF Q Q 3: P h e ba l-plat d: i its ream! Ward nd thehar fiiihas rag depending stud 74:1

which enters the forked extremityl-of the lat =1 eral m; 5 c a ;be1lcrank.-;suitably.inlillmea' b ea h h -.b d-ipiate and; prcvidedj with-the r enwardlyextending arm lecarrying the SRiI g7P BdnEiH ZZ- adapted teienhe the sle fital we Ze d h p leyeg li, 5 5 5 The 1 actuating 1 cambgtpfim in the can-4- tigqlling" cam --is ;so shaped-that; When the; arms fifiand fi0 ;are;conrietied by-meangwofl bemeupl g enier; 5,: he cu t r-blades 53 fifiaelvanee .plnralstag e movements-f to: isuccessively engage with their blmt'ri edged icrvyajrd extremities; first: the shuttle threadi and thenzfi loophf ineedlenfihreed tended by the shuttle, at Whfihdatterfistage: 3:301831'31165 space 45% resented 01 the; rolleres't ldti. Theipin 7 ha-v ingientened the 106578 of the-stop rlever 1 1, the? lateral threw Qffghhle latter --in effecting the final-- swppege ofthej machinemauses thezfinal-ac ti-iatienmf the cutterhlades tn bring their: cuttingedges intouoperatzive irelatiofl with the threads forseveringfthe sm le.- i:

Pi-vetally mountedlhy means biiitheserewe' sweetie pin-57:9 e w en he spa d ears of-th brabket fiQri' the h bs liofithe s arting l Yelgffilfmed wi h hea era aiier nred; arm BZ-eli dide pending arm; .83. normally; resting, upon the rearward edge fthe S E PJB-VQI'; & 1A1; a iacent depending arm 84 hasseeuned to; the side fa thereo y I means of the screw 8.5, s he to t.- fiei'of s a. torvvardly extending rigi arml- 8. he i g attached to its. apes turie ut r; end; the upper. extremityof... a spring 88 .eonnected at its-opposite end. to. the 8.9- hy means-pt Whichthestarting lever is normally maintained'in its 1111,1991 positionin which the arm;87 yieldinglyrrests upon the st0p-plnfi9-0 projecting from the bracket-arm Projectingfrom. the base .of the arm '87 is the stud91 having in its.o11ter end the gnider-screw92 j passing through the slot. 93 in the rearward. endof the link whose opposite? end isz pivotallyconnected at 95 With-the upper endof the-latch or detent-'' lever- 96; termed in its forward: edge with the noteh';9"Z-' .to afii'orc'l a latch shoulder and pia'otally; molmtedat. its lower end upon the stud-screw 98. The lever 96has adjacent its fiulcrurh point the rfearwardly extending hjook99 to-Which is connected one end of the spring-.100 having its oppositeend attached to the stud-screw 60 of. the coupling leverarm-59. Thei'spring. 100 serves to normally draw down the coupling levers-rm" 59 and thereby-effect the coupling of. the arms 4:6 and; when'inregister or overlapping. relation, while saidspring also actsto yielding'ly. press the latch-lever 96 into operative relationwviththearm 59 for prevention of such! {coupling action. 1

HIE-heupper, or outer-extremity of the couplilignlever 5.51111 3 uponr-one-of. its faces a laterailwing. v: Within inclined operative.

edgegnor mall-y lying within; the path of movement of each of. the lateral cam projections 101 :upon the. pl-ates 102' adjustably a secured upon the periphery of the camwl1eel;35-.by means of screws 103. By means otthes'eicam pro'ections, the disconnection of the-vibratory evers 46 and 50 is insured in each semi-rotation of the controlling cam, andgsuoh disconnection is maintained so long as the starting lever 82 83 is in running position with the lateral arm depressed, so aszto permit the latch-lever 96 to'snap into operative engagement with the coupling leverearm 59 to maintain the arm 55 retracted fromeng-agement with the lever 46, as represented in Fig. 1.

When the machine is at rest, the upper portion of the stop-lever 17 is thrown back- Wardly with its plunger-bar in engagement with the stopping cam, and, as represented infFig. 2, the plunger-pin 31 is in its lower operative relation with the detent-lever 33 and the coupling lever 55 is in couplin relation with the vibratory levers 46 and 50.

2P0: start aseem; :the z-latseratlaarrn fig-ei fthe eter ingileven is; drawn devvnwerdly no ning position wherein it is manuaHyiheld (hiring. jay-s itching periwistherehy iqrcing the 1 stop lever' 17 i .pzposition' whe ein t. isengagedand-detained by: meens of-the detent-lever-fiziai. The forward mevement; of. :the' starting-1 erefrerm p rmits the-edvganceot thelink 94c under the, action of. the spring 10th to cause; the detentr leyerj .96. g to .u on=-,-the side face of the ebupli'ng-levenaim The succeeding. engagement $015; the -;wi ng ,55' by one of the cam projections I0 1 causesizthe disengagement oft-he icoupling lever55=rorn the lever 46 and; the consequentrise of the. lateral arm 59 which is detained such retragcted position by; engagement? of the idejtent-lever 96, the upward smo vement' oi? the arm .59 beingseommunicated h)f: ;the pin-.62 to the S'lide banZ'Q. endhence et-he. .pl flg'ers pin. 3.1 which assumes; inoperatiye POSliilQLL above the stop-,m0tiondetent-lever 23; as represented in: Fig-1.1;; s the ctu ing-'- leveres perfo ms. itsvibratory movementszunder the action oi-the cam into: and; out of register-with the coupling lever 55, the latter-continues in itemtracted position under-the influence. of the latch-lever 9 se that .no threadwcuttin .:ac tion is; permitted; .while the elevation o%the plunger-pin 31, above the detent-lever 23v permitsits idleiendwise movement under. the; periodical action of? the stop-motion trip-- ping points 34:.- which are duplicated; as: are. other operative .partsofi the controlling cam; 35,; :as. represented in Fig; I 't; vvillbe ob.- sev edi that. t i q d ie ce -epp ed; to the; starting lever-arm 82 .y thei opeietor need be only; sufiicient-to OOHIltQIg-bELlBBBG. the 1m; pulse ofthe spring 88.,- ;thedetent-lever 23;

being maintained: in operative engagement- With the. stop-lever 17. during. substantially the-entire running period of .the maehinezso as to sustain the impulse of a the stop-lever 'When the starting lever. is released to per:-

mit the machine-to come to rest, it rises under-the impulse of the spring 88 upon the arm .8 7, thereby drawing back'wardly the link E94" anddisengaging' the-.deterrt-lever 96. from the coupling lever arm- 59 so as to per-- mit the couplinglever to assume coupliiig relation with the vibratory actuating lever- 926 'under the actionofthespring 100'as soonas the levers-4:6 and- 50. come into register in the continued movement of the'cam 35. i The descent of the coupling lever arm' 59 under the action of the spring 100 produces a like movement of the slide-bar 29 connected therewith, and hence of the plunger-pin 31 whose succeeding operative-movement under the action of one of the tripping points 34 causes the tripping of the-detent lever 23 to permit the stop lever :l'lto perform its normtil shutting zadti-cn 'iih ainjunction g i eem upai of in zp'tacticey the stop-screw 12 for. the: tewef cn geeiis st enses that the a rm- 5U into registeri :with the t eming- 46 when theletter asuiiiesi'ts ektreiiie ieer pcsitiion undeeythe iii'fluenee (ii th three-step es that mounting; pele tifinpis eetablished in such: e 2;treine trectedipositionabfthe'pertsq hs' the' csm eontinoesdts rttetitnr it impel-test -'the cutter cerrier 134;, through the-described con: netionsg eni "hence we: the itw'ccutter-bledes fifi 'aiid '66; twc;sta ge advance unovements one of; which :biifig'S the outteimbiade I 66 into; positioning iengegement 'with the lower or shnttle thresd= sent. the other firings the cut tef blad e-65 the medle threiil lea dis senate t-he shuttle and subsequently de- 'ee ited 'ehei tmetthe completion of which operationthesc11cwerstu tewithin one of on 'cleeiainee spsessne of the 20am groove. As the machinezoomes to nestthe stop+motion'.a- =It will be: bbserved ithat the reactuation of the starting lever foii' misus ceeding stitchingaperiodg does not in itself eifect the uncoupling of the levers. 46 and 50;

butimerel r' sets v the mechiinisin, including the I lat oh leiver 9-6,- :innerindition 'fore autematic actuation by means the cam pro l jeetions lOLefthecontrollingicem35;

zlhs shownnnd described therein; the cut-' ting elementsarewactuated :hy connectinns with both thescontrolling: com 3.5 ancl 'th'e stoppj'mg camupon-the mh-in shaft, but'it isevident: that the type? of cuttingdevice ems plolyed will determine whether-the stopping cantor especial form'; ofz-cezn driven by the nimin shaft shallbe employed either singly or 1jointly;to produce the operative move Inents of-the cutting elements; While according bottle-present disclosure cutting elements are employed for severi-ng' both-the upper and unden thread below the Work, it-is I essence trident white the chsrecteithe stitch; and ether conditions wlil determine the number locati n of the amingelements :to 'be' '2 Y ltgisevidefitthhtithe p1: "ntMpro've' fit isrsus'ceptib'le cf very meteizialsmedificstien iii-the constructionend airengement cfits cnnip'ofient "parts-within the-"scope. at the presentinvention; and that-the cf: sti'th ing meiiin nisin'and thst oi the threadazutt'mg etementsnnd isnecific e ctneting 'meens thefe fnn fshcwn' iind desciibed hefein are not es sentiafl theretot -.:2:Ha-ving-.3thus 'se'tnforth the nature of the infiention, what-I: claim-herein is I c 1. In a sewing machine, the combination ii 'ithiistitelirforming mechanism,- of threadcnitihg mechanism including it reciprocatory merniier,=-taictnating meens therefor includ ingfaconstantly 'a'activereciproeatory men-1- loer,hmsniially-eontholled meains for conpling-said members for reciprocation in unison; means for insuring against the repeated actuation of the cutting mechanism in consecutive stitchingcycles ot' the same stitohingperiod i ltn' 'a sewing machine the combination Wflifih: stitch-forming rnechavnism, of threadcutting; mechanism including a vibrator-yieven, iictuating mea ns' therefor including a; vibratory lever, manually controlled meansfier s coupling-'isaid levngsi- :forzlhcwenient inunison, and Pnieans- :ictin" ineleiwefidentl-y of saitl manual ly eontrolle i' m'eans tor effecting' the u-ncoupl-ingof said: levers." I

= 3'. In isse'wing mach-'nm the combination with 2t: .rotaryshe-ft end stitch-fuming mechanism operotively *conneoted there'- with, of thread cutting. mechanism: 11161115:- ing Hatreciprocatory ,member, actuating meims therefor including a rotary ca=m,-.-a reciprocetory follower therefor 'ancl' a i driv ing connection :b'et-weensaid shaft and cam foiuimpsirting :to the lattcr rotationsof less frequezzrcy than those of said-shaft, and manually -controlled means v including -anormally stationary lever operable while the machine is running for cheating the con pling and uncoupling of-the reciprocetory inei-nberwitlr said follower for movement in unison therewith.

L In a sewing. machine, the combination with stitch-forming m'echenism, 0% thread-- cutting mechonism'including. a. cutting ele meat-having a. range of. movement entirely atone side of the Work and a=reciprocatory member operntively connected therewith, actuating means for said mechanism including a constantly active reciprocatory member and means including a spring-actuated coltpling element and a 'manually controlled latch therefor tor effecting the coupling of said members for'reciprocation iii-unison.

5'. In a sewingqnach'ine, the combination with stitch-forming mechanism, a stop-motion therefor, and a starting lever for operating the stop-motion to start the machine, of a thread-cutting device, actuating means therefor, and means connected with said starting lever independently of the stop-motion for efliecting the coupling of the thread-cutting device with its actuating means.

6. In a sewing machine, the combination with stitch-forming mechanism, and a stopmotion therefor including a spring-pressed stop-lever and a detent therefor, of a threadcutting device, actuating means therefor, a spring-actuated coupling element for operatively connecting said cutting device with its actuating means, a detent for said coupling element, and manually controlled means for disengaging said detents from the stop-lever and coupling element, respectively.

7. In a sewing machine, the combination with stitch-forming mechanism, and a stopmotion therefor including a spring-pressed stop-lever and a detent therefor, of a threadcutting device, actuating means therefor, a springactuated coupling element for operatively connecting said cutting device with its actuating means, a detent for said coupling element, and means including a manually controlled lever and independent connections between the same and said detents whereby they are disengaged from said stop-lever and coupling element, respectively.

8. In a sewing machine, the combinatio with a shaft, stitch-forming mechanism connected with and actuated by said shaft, and a thread-cutting device, of a cam permanently connected with said shaft, a reciprocatory follower therefor, a reciprocatory member connected with said thread-cutting device, a coupling element for connecting said follower and reciprocatory member, and

manually controlled means for operating said coupling element.

9. In a sewing machine, the combination with a shaft, stitch-forming mechanism, a stop-motion for controlling the operation of said shaft, and a thread-cutting device, of a cam permanently connected with said shaft, a connection between said cam and the thread-cutting device and comprising two independently movable members with a coupling element for connecting them together, and manually controlled means for rendering said stop-motion and coupling element active or inactive in the performance of their respective functions.

10. In a sewing machine the combination with a shaft, stitch-forming mechanism, a stop-motion for controlling the operation of said shaft, and a thread-cutting device, of a cam permanently connected with said shaft, a connection between said cam and the thread-cutting deviceand comprising two independently movable members with a coupling element for connecting them together, stop-motion tripping means on said cam, and manually controlled means for rendering said tripping means and coupling element either effective or ineffective in performing their respective functions.

11. In a sewing machine, the combination with a shaft, stitch-forming mechanism, a stop-motion comprising a spring-pressed lever for controlling the operation of said shaft, and a thread-cutting device, of a cam permanently connected with said shaft, a connection between said cam and the threadcutting device and comprising two independently movable members with a coupling element for connecting them together, a detent for said spring-pressed lever of the stop-motion, a tripping element carried by said cam, and manually controlled means for effecting the establishment and interruption of operative relation between said tripping element and detent and between said coupling element and said independently movable members.

12. In a sewing machine, a thread-cutting mechanism comprising a cutting element, levers having a common fulcrum upon which they are independently movable. a cam for operating the one and a connection between the other of said levers and said cutting element, coupling means for connecting said levers for movement in unison, and means for insuring action of said coupling means at 2i predetermined stage of a stitch-forming cyc e.

13. In a sewing machine, the combination with stitch-forming mechanism, and a stopmotion therefor, of thread-cutting mechanism including a reciprocatory member, actuati'ng means therefor including a constantly acting reciprocatory member, means for coupling said members for reciprocation in unison, and manually controlled means for actuating said stop-motion and coupling means in the same stitch-forming cycle.

In testimony whereof, I have signed my name to this specification, in the presence of two subscribing witnesses.

WILLIAM L. BARRON, HENRY A. KOMEMANN, Jr.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. C. 

